Evidence in the Bank of Japan's "tankan" survey that companies are growing more pessimistic may prompt the central bank to expand support as soon as next week for businesses grappling with the yen's advance.

The BOJ is likely to increase its ¥30 trillion credit program for lenders at its Policy Board meeting Monday and Tuesday, analysts say, to encourage bank lending and reduce demand for yen after the government last month intervened in the currency market for the first time in six years.

The facility has so far failed to arrest declines in lending and consumer prices, and enlarging it won't increase demand either, analysts say.